This invention relates to a rotary cylinder or a rotary drum for an epilating appliance, having at least two clamping elements arranged adjacent to each other.
From international patent application PCT/EP96/04915 there is known an epilating appliance equipped with a rotary cylinder having a multiplicity of clamping element pairs which are offset at an angle to each other. With the aid of pressure pins the clamping elements are moved during rotation of the rotary cylinder so that in the area of a plucking zone they are brought pair by pair into clamping contact. Any of the user""s hairs lying between the clamping elements will be plucked by the further rotary movement of the rotary cylinder.
It is desirable for at least one of the clamping elements to be made of a hard material such as metal in order for the hairs to be reliably gripped and extracted. This may result in a metallic noise occurring when the two clamping elements strike each other. The use of a softer and hence quieter material is not readily possible because then reliable gripping of the hairs would no longer be guaranteed.
It is an object of the present invention to provide a rotary cylinder for an epilating appliance which is efficient and quiet as regards the removal of hairs, developing in particular less noise than conventional rotary cylinders while still enabling the reliable gripping and plucking of hairs.
According to the present invention this object is accomplished with a rotary cylinder of the type initially referred to by providing mechanisms for damping the noise which are associated with at least one of the clamping elements.
In an advantageous aspect of the present invention provision is made for an intermediate layer between one of the two disks and the adjacent clamping element or between the adjacent clamping elements themselves. The resulting reduction of noise is based on the joint damping effect, according to which the micro movements occurring in a vibratory system in joints, that is, in the area of component interfaces, are converted by friction into heat (Coulomb""s friction) and severely damped in the process.
Preferably the rotary cylinder is provided with at least two adjacent disks having on their facing sides a groove for forming a clamping element receiving space in which at least one clamping element is arranged.
In a further advantageous variant the intermediate layer is constructed as a component of the clamping element on the clamping element""s side close to the disk. This may be accomplished, for example, by the clamping element being roughened, the roughened layer then forming the intermediate layer.
In yet another advantageous variant the intermediate layer is constructed as a shim. It is thus possible to adapt the intermediate layer to the clamping elements with a view to achieving an optimal noise reduction. In particular the shim can be specifically selected and constructed as regards its material and size.
In both variants, at least one of the two facing clamping elements is movable, with the intermediate layer being associated in particular with the movable clamping element.
In this arrangement it is particularly advantageous for the production process to allow for a clearance in the clamping element receiving space between the disk and the movable clamping element and for the clearance to be filled by the intermediate layer. In other words, a clearance already existing for production reasons between the disk and the movable clamping element is used to position the intermediate layer there. No technical changes need to be made therefore to the rotary cylinder, and even former rotary cylinders can be readily equipped with the intermediate layer of the invention.
It is also an advantage for the intermediate layer to be of an elastic construction. Particularly the movable clamping element will not be obstructed therefore in its free mobility when the intermediate layer is inserted.
Among other materials, paper and/or sand paper and/or plastic and/or sponge rubber and/or the like have proven practical as the intermediate layer.
In a further advantageous and separable embodiment of the invention, which can also be applied independently of using the intermediate layer, at least one of the two clamping elements has two outer laminations and at least one intermediate lamination in between. The clamping element thus has a type of sandwich structure, with the various laminations being firmly joined together. If the clamping element is incited to vibrate, the vibratory energy will be converted in the intermediate lamination into heat (via shear stresses), thus reducing vibrations and noise. Hence the clamping element produces less structure-borne noise and air-borne noise and the development of noise is reduced.
It is particularly advantageous for the intermediate lamination to include a polymer, in particular an adhesive. It is also particularly advantageous for the outer laminations to include a metal, in particular steel.
If noise reduction is the sole concern, a symmetrical design of the sandwich structure with identical thickness of the outer laminations will be preferred. However, it is also necessary to consider the clamping action of the sandwich structures, particularly with a view to their deflection. Hence in an advantageous further aspect of the invention the thickness of the outer laminations varies because this enables the clamping action to be optimized without substantially impairing the degree of noise reduction.
In a further advantageous, separable embodiment of the invention, which can also be applied independently of using the intermediate layer or the sandwich structure, the at least one clamping element is adapted to be acted upon by two pressure pins, with the noise damping mechanisms being associated with the pressure pins. A particularly effective and extensive damping of the noise can be achieved by associating the noise reduction mechanisms with the pressure pins. This noise damping can be performed as an alternative or addition to the noise damping measures previously referred to. Hence it is possible on the whole to achieve an extensive reduction of noise in return for only a small additional outlay.
It is particularly advantageous for the two pressure pins to be actuatable by a thrust plate and for the noise reduction mechanisms to be arranged between the pressure pins and the thrust plate. This arrangement is particularly well suited as an additional measure to the noise damping measures previously described.
In an advantageous further aspect of the present invention a damping disk is provided as a noise reduction mechanism. This damping disk requires only a small outlay to achieve the reduction of noise in accordance with the invention.
Conveniently, in this arrangement the damping disk is made of a metal, in particular of a spring steel, or of a plastics material, in particular a flexible plastics material.